The present invention relates to a control or adjustment system for a wheel brake operated by an electric motor.
A system of this type is described, for example, in U.S. Pat. No. 4,995,483. The brake concerned is an aircraft brake.
An application force of the wheel brake is determined to satisfy the demand for deceleration of the operator of an aircraft or a vehicle. A servo motor is actuated until a determined adjustment travel of the actuating member is reached, the measurement starting with the first contact of the brake lining with the brake disc.
This provision is not sufficient to sensitively slow down the vehicle. Admittedly, there is a basic relationship between the displacement travel of the adjusting element and the application force. However, the application force may vary due to external influences and, in addition, the brake torque to be achieved is not absolutely linked to the application force.
After it has been fixed that the brake lining is declamped from the brake disc upon release of the brake, the motor is still energized for a certain period of time so that the brake linings are further removed from the brake disc. The clearance which is caused by this action is not defined precisely because the clearance is not specifically linked with the energization time of the motor.
Therefore, the object of the present invention is to provide an improved system of sensitive braking and reliable adjustment of an accurately defined clearance.